Paper-making.



W. H. MILLSPAUGH.

PAPER MAKING.

APPLICATION FILED OCT. 1. 1909.

1 1 63,25 1 Patented .Dec. 7,.- 1915.

6 SHEETS-SHEET I.

sv wenfoz w. H. MILLSPAUG-H. PAPER MAKING.

APPLICATION FILED OQT- 7- 1909.

1,163,251; Patented Dec. 7, 1915.

6 SHEETS-SHEET 2.

W. H. MILLSPAUGH.

PAPER MAKING.

APPLICAHON FILED OCT- T, 1909.

1,163,251 Patented Dec. 7, 1915.

6 SHEETS-SHEET 3.

W. H. MILLSPAUGH.

PAPER MAKING.

APPLICATION FILED 0017. 1909.

V Patented Dec. 7, 1915.

6 SHEETSSHEET 4.

v WITNESSES W a Ka /C.

W. H. MILLSPAUGH.

PAPER MAKING.

APPLICATION FILED OCT. 7. I909.

Patented Dec. 7, 1915.

6 SHEETS-SHEET 5.

Patented Dec. 7, 1915.

6 SHEETS$HEET 6 Svwanfov flmmu,

WILLIAM H. MILLSPAUGH, 0F SANDUSKY, OHIO.

PAPER-MAKING.

Specification of Letters Patent.

Patented Dec. 7, 1915.

Application filed October 7, 1909. Serial No. 521,536.

To all whom it may] concern Be it "known that I, WILLIAM H. MILL- sraUofi', a citizeii'of'the United States, residing at Sandusky, in the county of Erie and State of Ohio, have invented certain new and useful Improvements in Paper-Making; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to practise the same.

This invention is an improvement in the art of making paper, and its objects are greater efficiency and economy in manufacture, increased speed of production, and improvement of the product.

My invention involves a new process of aper-making and means therefor constituting an improvement in paper-making machines, more especially applicable to Four drinier machines, which greatly increases their capacity, improves their operation, and also simplifies the construction of such machines by eliminating parts now commonly and necessarily employed therein and also enabling a reduction or even omission of the press felts and reduction of the drying section.

In the present art of manufacturing paper, either on cylinder or Fourdrinier machines, the transformation of the pulp or paper stuff into a moist sheet of paper fabric and rendering the same in condition for delivery to the drying rolls is effected by a process of repeatedly expressing or squeezing out water from the sheet. Necessarily the removal of water from the sheet by pressure cannot practicably, effectively and econonu'cally be carried on beyond a limited degree, and the excessive amount of moisture retained in the sheet before going to the driers necessitates the use of a large drying equipment and large consumption of steam, besides being a factor in the capacity of the driers and hence limiting the speed and output of the machine.

Rapid or toosudden steam-drying is objectionable; it is well known that a sheet of paper is stronger, smoother and better when dried by low steam pressure; which however retards the output in accordance with the amount of moisture needingto be evapo rated. On the'other hand, under some conditions the capacity of the driers may be equal to or greater than the speed at which the sheet can be handled off the wire and through presses, the speed and production of the machine being limited accordingly by the time required for expressing Water from the sheet, particularly in work on some kinds of slow stock.

Besides providing a more efficient and economical method, my invention obviates or substantially simplifies many of the problems which confront the industry to-d'ay.

In order to facilitate a clear understanding of my invention it should be observed that the drying effect on a sheet of paper forming on the making-wire of a Fourdrinier machine results not from atmospheric pressure upon the external portion of the sheet while passing over suctionboxes, as has been commonly supposed, but from the passing of air through the sheet; and I have discovered by many costly experiments that a much greater volume of air can effectively be drawn through the wet web or sheet than has heretofore been supposed practical, with remarkable results in the drying of the web and in the texture and condition of the web or sheet so dried; it is essential, however, that the air be passed uniformly through all portions of the sheet for. perfect results.

Based upon my experiments and discoveries, I proceed on a radically different principle from the present process of making paper by repeatedly squeezing out moisture between rolls. In my process the pulp is converted into a sheet of paper of the requisite or desired percentage of dryness for steam drying (higher than attainable with previous methods), notby expressing mois ture by mechanical compression, but by abstracting the water and moisture and drawing large volumes of air uniformly through the sheet by vacuum; the layer of pulp which has formed upon an endless wire cloth or other suitable porous wet web carrier, preferably the making-wire of a Fourdrinier machine,being subjected to the vacuum treatment while upon the wire or carrier, or both before or after leaving the wire (depending upon the nature of the work and percentage of dryness required), by passage" over one or more revolving suction-rolls, whlch may be of any form suitable for main.- taining vacuum on a portion of cyllndrical surface, the suction-rolls being in communication with a vacuum pump or pumps capable of maintaining a substantial uniform or constant vacuum in the suction-chamber or chambers of the rolls while handling large volumes of water and air; whereby the layer of pulp is matted or consolidated by the atmospheric pressure and draft of air through the web, and by the forcing of such large volumes of air uniformly through the sheet the same is evenly and very effectively treated and rendered dryenough for passing through press rolls without crush (either with or without felts, depending upon the nature of the work and thickness of the sheet), such press rolls being em ployed in some instances for pressing or smoothing the sheet while in some cases the sheet is passed directly to the drying cylinders.

The described treatment by vacuum 15 preferably continued or repeated as far as may be economical, efficient or desirable for drying the paper in this manner; and at such step in the progress of the work as will not injuriously affect the fiber heated air is or may be introduced in contact with the surface of the sheet and in such manner as to be drawn through the sheet by suction, for absorbing remaining moisture; after which the sheet is or may be carried through the presses and thence passed over the drying cylinders or other drying means in the usual manner; but in many cases it will be desirable to omit the hot air treatment; and in making certain grades of paper, more particularly tissues and other light Weights, the extent of vacuum treatment necessary will be less than in the manufacture of paper of heavier or thicker grades, and the nature of the stock being treated will also affect the extent of the treatment, wherefore in some instances a single suction-roll and in other instances a plurality or series of suction-rolls will be employed.

By the foregoing method, the sheet is delivered to the presses, if employed, and to the drying cylinders much drier or containing a much smaller percentage of moisture than is possible with former methods, and also in better condition for steam drying with best results, thus facilitating the drying operation and increasing the capacity of the driers and augmenting the speed and production of the machine; production being also increased by elimination of. frequent sources of breaks in the wet web at the couch-rolls and presses; and I also produce a better grade or quality of paper, uniformly dried and of smoother finish, free from wiremarks and felt marks, hence of uniform smoothness on both sides, and Without other imperfections which frequently arise in the practice of the present methods of making paper as heretofore explained. By the meager forceful drawing of large volumes of air uniformly through the continuously travelmg web or sheet, the latter is thoroughly and uniformly treated, thus relieving the art from the exactions of uniform pressing and the well known difficulties of uniform drying; and by eliminating the usual operation of squeezing the wet web by the top couch roll the sheet is taken from the making-wire with an entire absence of wiremarks, and by substantially drying the sheet before going through the presses the usual felt marks are also eliminated or practically invisible and if perceptible at all will be removed by the driers and calenders; however, the practice of my invention renders the calendering unnecessary in many cases; in fact in many instances the paper produced by my process is superior in qual- 1ty and smoothness, even if uncalendered, to calendered papers produced by former methods.

I will now refer to the accompanying drawings wherein I have diagrammatically represented suitable means for practising my invention, which however may be carried out in various ways and the number and arrangement of the suction-rolls varied 1n accordance with the nature of the stock or the grade and thickness of paper being manufactured; it being impractical to illustrate all of the 'numerous arrangements of machinery by which my process may be performed, and hence I do not restrict myself to any specific machine or arrangement.

In'said drawings: Figure 1 is a diagrammatic view of a F ourdrinier paper-making machine modified and embodyingcertain improvements in accordance with my invention, and by which my new method or process of making paper can be practised; the machine illustrated in this figure being designed more especially for the manufacture of tissues and light weight papers, and the drying section being adjacent to the makingwire and the presses and press felts being omitted. Fig. 2 is a similar view of a machine for like work, where the driers are removed from the making-wire, the presses intervening but the sheet being carried by the felts over the presses, showing an arrangement whereby a F ourdrinier machine suclr as ordinarily used in the art may be modified to suit the requirements. In this view the major portion of the wet end of the machine is omitted, only the delivery end of the wire with the suction-roll taking the place of the usual lower couch roll being shown. Fig. 3 is a diagrammatic view of what I at present consider a preferred construction for the manufacture of light Weight papers and by which a calendaring equipment is rendered unnecessary and may be dispensed with. Fig. 4 illustrates a modification of the machine shown in Figs. 1 and 3. Fig. 5 shows'the suction-roll at the delivery end of the making-wire in con unction with a dandy or smoothing roll. Fig. (3 shows a suction-roll in conjunction w th a hood for application of heated air. Fig.7 shows a suction-roll in conjunction with a spraying appliance for furnish ng coloring or other matters. Fig. 8 is a diagrammatic view of a Fourdrinier machine equipped with a series of suction-rolls; this machine being designed more especially for the manufacture of medium and heavier grades of paper. This view illustrates so much of the machine as precedes the usual steam timers, and the sheet is shown passing through the usual series of three presses for smoothing purposes, the first press felt being employed and the others omitted; though it is understood from preceding remarks that the press felts may be entirely discarded in some cases. Fig. 9 is an enlarged sectional view of that portion of the machine of Fig. 8 by which the sheet of paper is sub ected to vacuum. Fig. 10 is a view similar to Fig. 9

vof another form of apparatus.

In the drawings, 1 indicates the makingwire which passes over a breast roll 1 and over the suction-roll 2 (located in placepf the usual lower couch roll), and over an 1ntermediate series of table rolls supporting the upper run of the wire, as usual in such machines; the lower run of the wire passing over suitable guiding and tensioning rollers as usual. The deckle straps 1 running over pulleys 1 are arranged above the makingwire as usual.

1 is a dandy roll, and 1 a guide roll.

The Fourdrinier part or wet end of the machine is or may be substantially as in any ordinary Fourdrinier machine, except for substitution of the suction-roll 2 in place of the usual lower couch-roll, eliminatingthe top couch-roll with its accessories, and elimination of the usual equipment of flat suction-boxes or all except that one (1) required to remove water for dandy roll purposes, or to hold the edge of heavy or slow sheets between the deckles and the suction roll on such machines as may not be equipped with deckle-straps extending down to the suction-roll.

Elimination of the top couch roll avoids the serious objections of frequent renewals of the'expensive woolen couch-roll jackets; theoccasional breaking of the wire by the bursting of such ackets, or the rupture of the web of paper by clinging to such acket, and also avoids injury to the wire by the passage between the wire and thetop couch roll of any hard lumps or foreign matter which may fall upon the wire; and by eliminating the flat suction-boxes the wear and drag on the making-wire are greatly reduced, prolonging the life thereof very materially, and by reducing friction less power 1s required to operate the wet end of the machine.

Referring to the suction-roll, which may be of any form capable of maintaining a vacuum on a portion of cylindrical surface, usually such an area as to subject a considerable portion of the web or sheet to influence of Such vacuum, I prefer in view of the heavy vacuum maintained to employ a suction-roll having provision for maintaining its suction-chamber or chambers (2 in air-tight contact with the inner surface of the revolving shell or cylinder, so as to effectively utilize the vacuum, and for limiting the pressure of such contact to prevent the suction-chamber or chambers from becoming locked to the shell or cylinder under influence of vacuum, with consequent wear, chatter and increased driving power; whereby I am enabled to operate the suction-roll safely while maintaining such heavy and substantially uniform vacuum as is necessary to pass the desired large and constant volumes of air uniformly through the web or sheet and to cause the external air pressure upon the web to lock the making-wire 1 to the suction-roll 2, so that the means which rotate the latter may also be utilized for driving the making-wire. I prefer at present a construction of suction-roll substantially as shown and described in my U. S. Patent No. 895,281, dated August 4, 1908, though I do not limit myself thereto. A slotted or perforated pipe 2 may be introduced into the suction-roll and used for jetting air or steam for blowing or stripping off the sheet at the proper point, doing away with picking off the sheet by hand; the air delivered from said pipe passing through the apertures or perforations in the roll and striking the inner side of the paper.

Through suitable pipe-connections the suction-roll is connected with an air pump or pumps, as at P (Fig. 1), capable of maintaining a substantial constant vacuum or continuous high-pressure uniform draft in the suction chamber or chambers of the roll while handling large volumes of water and air; the pump being preferably a high power positive rotary vacuum pump (as described in my pending application for patent for an improvement in paper making machines, filed October 7, 1909, Serial No. 521,535); and by this means the water is abstracted and such large and constant volumes of air are drawn uniformly through the pulp course or wet web in passing over the suction-roll as will remove practically all free moisture from the web and consolidate the same into a sheet of paper; all portions of the sheet being moreover uniformly and thoroughly treated. due to the uniform pressure upon and draft of air through the sheet; while at the same time the pressure upon the outer surface of the sheet locks the makingwire to the roll which is thereby enabled to drive the wire accurately and effectively, doing away with supplemental driving means. By the described treatment, the sheet is taken from the making-wire with a much smaller percentage of moisture than when delivered from the couch rolls of an ordinary I ourdrinier machine, being delivered in some cases as a damp sheet of paper, i. 0. containing a certain percentage of evaporable moisture, and may be passed over or in contact with additional suctionrolls for further vacuum treatment or may be treated by heated air either separately or in conjunction with the vacuum treatment, different methods of treatment being appropriate for different grades of paper; and in some instances, depending largely upon the nature of the stock and work, the thickness and character of the paper, and the percentage of dryness needed, the sheet acquires such integrity and dryness at the suction-roll 2 as to be taken directly to the drying cylinders, as exemplified in Figs. 1 to 3 of the drawings. In said Figs. 1 to 3 inclusive, a series of driers are indicated by the symbols D D etc., and the drier felt by the letter d. In Fig. 1, the driers are adjacent to the suction-roll and the sheet blown off from the roll is taken upon the drier felt over the guide roller (Z passing thence under the first drier and around the succeeding driers in the manner illustrated. Fig. 2 shows an arrangement whereby the sheet may be carried from the making-wire to the driers when remote from the wire, as in the usual Fourdrinier machine where the presses intervene; illustrating a manner of equipping or transforming an ordinary machine for the practice of the invention. In this figure only the first and second presses are shown, being denominated P and P while F denotes a press felt. The press felt F is guided to carry the sheet over instead of through the presses, and to drive the felt and give it the proper direction of movement its lower or reverse run may be passed through one or more of the presses, the usual direction of rotation of which is reversed, as indicated by the arrows; such presses (the second press in the figure) being thus used for running the felt while the remaining presses may be inoperative. In Fig. 3, I have illustrated a very desirable arrangement for the practice of my method, which is especially efficient where the calendering is to .be dispensed with. In this construction one or more smoothing rolls or so-called friction rollers, R and R are arranged to coact with the driers upon the sheet, thus smoothing and ironing out the sheet.

' With some kinds of fiber and when making certain kinds of sheets, it is often desirable to use a roll to assist in closing the sheet and laying down the wild fiber. This can best be accomplished after a portion of the water has been extracted from the sheet and, therefore, I find it of advantage to place this roll in contact with the sheet overthe active surface of the suction-roll, as illustrated in Fig. 5 where the smoothing roll is denoted by the letter R. The position of this smoothing roll will ordinarily be adjustable so that it may be placed at the most effective point. This may also represent a dandy roll which may carry marking devices, or emblems such as type metal, rubber or other material, and may be adjusted or set forward or back as desired, the sheet of paper being wetter where vacuum first begins than it is at a point further advanced. Very desirable results may be secured in marking a sheet of paper at this point, as there is no danger of picking the sheet from the wire, due to the large volume of air passing through the sheet with the vacuum in the chamber underneath holding same firmly to the wire. In place of or in addition to the roll B (Fig. 5), the sheet may be taken from the suction-roll through one or more coacting pairs of smoothing rollers or friction rolls 1' (Fig. 4c).

In Fi 6 a hood 2 is shown arranged over the suction-roll opposite the vacuum chamber or chambers therein and may be supplied with heated air by a suitable pipe, or the air can be heated in the hood by steam pipes or other suitable means. This hood will largely block off the moist cold atmosphere from the room and the larger volume of air drawn through the sheet will be the hot dry air in the hood. By this means the drying operation may be carried to a still higher degree before the sheet leaves the making-wire, in cases where this treatment may be practical or desirable.

I will now refer to a more extended application of my process, as exemplified in Figs. 8 to 10 inclusive, wherein the treatment of the sheet by vacuum in the manner already described is continued or repeated, with or without subjecting the sheet to the action of heated air; the methods hereinafter outlined being more particularly adapted for the manufacture of heavier or thicker grades of paper, or where the nature of the work is such as to require the delivery of the sheet to the driers at a still higher percentage of dryness. In said drawings Figs. 8 to 10 inclusive, the Fourdrinier part or wet end of the machine is or may be substantially the same as in the preceding figures, the driers (not shown) being removed from the wire; and, instead of the usual first press felt for receivin the paper from the delivery end of the ma ing-wire, I provide the plurality or series of suction-rolls 3, 4, each containing one or more suctionboxes or chambers 3*,4 (and blow-ofi pipes 3", 4 for stripping the sheet), said suctionboiges extending preferably through such an are or angle as to subject a considerable portion of the Web or sheet to the action of the vacuum maintained therein; and the suction-roll 3, also roll 4, if desired, may be covered with wire cloth 3" to prevent the baresheet of paper taken from the roll 2 from being sucked into the holes or perforations in the roll. Instead of wire cloth, it would be practicable to use a covering composed of porous material such as felting, stone, etc., although the wire covering is the simpler and preferable form, such a covering being in common use in paper mills for making board and in pulp mills as a cylinder-mold covering. In the suction chambers of the rolls, heavy uniform suction or vacuum is maintained for drawing large volumes of air through the sheet, in the manner and by means as already described, which vacuum in some cases may be advantageously at different pressures in the different chambers, for example there may be a graduation or variation in degree of vacuum to which the sheet is subjected at different points in its progress.

In operation, the layer of pulp which has formed on the making-wire passes on the roll 2 over the suction-box or suction-boxes 2 thereof and by subjection to high uniform vacuum at this point is compacted or condensed into a sheet and substantially all free water or excess moisture is removed therefrom, so that the sheet is delivered as a damp sheet of paper; which may have however a smaller percentage of moisture than when delivered from the usual couch rolls of a Fourdrinier machine; all portions of the sheet being uniformly and thoroughly treated as aforesaid, and from the suctionroll 2 the sheet is taken on the suction-roll 3, passing over the suction-box or boxes 3 therein, and by the continued drawing of large volumes of air uniformly through the sheet the drying process is carried to a further extent, yet without any squeeze or rolling, so that the fibers are not subjected to compression between unyielding surfaces at this time, as in the ordinary process of paper making; and the sheet passes from the suction-roll 2 in a much drier state than after it has passed through the last press of the ordinary Fourdrinier machine, with the advantage, however, of having been dried by passage of air by vacuum through the sheet. From the suction-roll 3 the sheet is or may be taken on the suction-roll 4, whereat the operation of drying the sheet by vacuum is still further advanced. The arrangement is preferably such that the roll 4 operates on the reverse side of the sheet, that is, the suction-rolls 3 and 4 operate on opposite sides of the sheet. Thus, where the and absorb remaining moisture; the sheet having now been suiiiciently dried by the suction-rolls 2 and 3. that it is in best condition for this treatment, as the hot air can .loe drawn through the sheet after it has reached a certain stage of dryness without injury to the fiber. For this purpose the suction-roll 4 is shown equipped with a hot air hood 5 which may be supplied through pipe 5f from a suitable heater, or the air can be heated in the hood by steam pipes or other-suitable means.

After passing from the suction-rolls the sheet of paper may be carried through pressrolls for pressing and smoothing same preparatory to going over the drying cylinders; and as previously stated the sheet may be run through the presses with or without felts, depending upon the nature of the work and thickness of the sheet; for owing to the integrity and dryness of the paper fabric, imparted by the action of the air at the suction-rolls, on certain grades of work the sheet can be run bare through the first and remaining presses, not needing the assistance of felts or tapes, but ordinarily, and especially in making book and news papers and other papers of light and medium thickness, the use of the first press felt will be found needful or desirable, as represented in the drawings (Fig. 8) where the sheet is shown taken from the suctionroll 4 upon a press felt 6 through the first press roll 7 and thence carried bare through second and third press rolls 8 and 9, after which the sheet is or may be passed over the drying cylinders in the usual manner.

The press felt 6 on which operates the well known shower pipes 6 and rubbercovered squeeze-rolls 6 to permit continuous cleansing of the felt is shown running over a small suction-roll 6 for drying the felt before the paper meets the same and over a suction-roll (i to flatten the sheet of paper down on the felt and draw the air out from between the paper and the felt so that the paper will not blow at the press rolls. The illustrated arrangement of the press felt and rolls and accessories is not a feature of the present invention, being reserved for a separate application.

In view of the different treatments that may be required for different grades of pacases it will be desirable to carry the paper from the suction-roll 3 through one or more press rolls, then over the suction-roll 4, thence through additional press rolls or directly to the driers; or other suction-rolls may be incorporated, arranged successively or alternating with press rolls; and the application of hot air may be varied, or it may be dispensed with, according to the nature and quality of the paper being made. Other suction rolls than j and is may be incorporated and the process of drawing hot air through the paper may be continued. until the point is reached in the process of manufacture where it is not desirable, economical or efficient to continue the drying in this manner, after which the paper may be passed through the press and to driers or taken directly over the drying cylinders or other drying means.

It is well known in the industry that ordinary drying cylinders are not eflicient as a means for transferring heat tothe sheet and drying the same, because not more than forty-five to fifty per cent. of the surfaces of the drying cylinders are actually in contact with the paper, the balance radiating heat into the atmosphere; whereas with the method herein set forth all the heat or the major portion of the heat is carried through the paper, absorbing moisture and resulting in great economies in the use of the same.

Especially satisfactory results may be obtained by extending the distance between the suction-rolls 10 and 4 and applying hot or heated air to the surface of the sheet of paper therebetween. In this connection, I have shown a highly efficient apparatus in Fig. 3, adapted to take the place of the section of the machine shown in Fig. 9. In this apparatus the suction-roll 2 is arranged at the delivery end of the making-wire 1 as in the first construction. Adjacent thereto is a suction-roll 10, and at a distance be hind the same is a suction-roll 11, said rolls 10 and 11 corresponding with rolls 3 and 4 in the first construction. Around them runs a wire cloth or common Fourdrinier wire 12, similar to the making-wire 1. On the under side of this second wire 12 is an air-tight box or chamber 13, having adjustable sides, into which air is supplied by a pipe or pipes 13 at the dry end of a box, that-is the end nearer the driers or farther from the wet end of the machine, while the opposite or cold end of the box is or may be provided with an adjustable gate or valve 13". Deckle straps 13, may run on the top of the sheet on this second wire to hold the edges of the sheet from lifting from the wire under the action of the hot air, or a second endless wire may be arranged to lie fiat upon the sheet of paper and hold it down. The suction-roll 11 is shown provided with a hood 14 for hot air. In operation, the sheet taken from the making-wire is passed on to this second wire 12, and atmospheric air is drawn through the sheet in passing over the suction-box 10 of the suction-roll 10; and in passing over the box 13 hot air is applied to the under side of the sheet, at a gradually increasing temperature due to the arrangement of the hot air supply pipes 13; and in passing over the suction-box 11 of the suction-roll 11 the sheet is exposed on its opposite side to hot air in the hood 14 and the hot air is drawn. through the sheet by the vacuum in the manher already explained, after which the sheet is run bare or on felts through the presses and next to the driers as before described.

By the process herein set forth, it is entirely possible and practicable to produce a sheet of paper drier before going over the drying cylinders than after it has passedthrough fifty per cent. or more of the drying-cylinders of an ordinary Fourdrinier machine of large drying capacity; by which it will be seen that the capacity of the driers may be enormously increased, or a shorter equipment of drying section may be employed; and by continuing the process outlined it may be practicable to completely dry the paper in this manner and dispense with the use of drying cylinders except such as may be needed for smoothing, ironing or calendering the paper.

It will be evident to any practical papermaker that the suction-roll 2, as well as the suction-rolls 3 and 4, on other suction-rolls that may be incorporated in the machine, offers an almost unlimited field for the application of size, color, water-proofing or parchmentizing; the necessary substances being applied to the sheet where the latter is acted upon by vacuum. Thus liquid for coloring may be applied either in the form of a spray or with rolls, baths or other well known means, the coloring being drawn into the sheet uniformly by virtue of the heavy uniform vacuum so as to thoroughly permeate the paper. This permits changing color on the machine without changing stock or washing up screens, pipes, etc. The ordinary method of coloring papers being to color the stock in the beater. Sizing or hardening compounds may be applied to the sheet in. the same manner, the compounds being drawn thoroughly into the sheet and mingling with the same by the air current. This results in a saving of sizing material and applies it in the most practical manner. This feature will be found very desirable in making water-proof papers. Certain glues and other elements can be drawn into the web of paper, permeating the same and.

mas er With present methods of making waterproof papers it is necessary for the presses to take out the surplus of glue or waterproofing materials, but with my invention there will be no surplus to be removed by the presses as the proper amount is fed to the sheet at all times and drawn in by the suction-roll.

Fig. 7 shows a shower pipe for spraying coloring or other matters opposite the roll 2.

Having thus described my invention what I claim as new and desire to secure by Letters Patent is:

1. The improvement in the art of manufacturing paper which consists in subjecting a layer of pulp in its passage through the machine to the action of a large volume of air drawn by vacuum uniformly through the sheet, whereby the water is extracted and carried off by absorption and physical contact with currents of air passing through the pulp without the aid of compression.

2.- The improved process of making a paper web on a paper machine which consists in forming the sheet and extracting its moisture by drawing large volumes of air uniformly through the sheet by vacuum, whereby a sheet is produced in condition for successfully passing the same through the succeeding drying processes by absorption and physical contact with air drawn through the paper web in its passage through the machine unassisted by mechanical compression.

3. The improved process of making a paper web on a paper machine which consists in forming the sheet and extracting its moisture by forcing large volumes of air uniformly'through the sheet and applying heated air thereto to assist in the drying of the sheet, whereby the extraction of the water is efiected by absorption and physical contact with air passing through the web and a sheet produced in suitable condition for successfully passing the same through the succeeding drying processes unaided by mechanical compression.

4. The improved process of making a paper web on a paper machine which consists in forming the sheet and extracting its moisture by forcing large volumes of air uniformly through the sheet and forcing heated air through the sheet after it has been partially freed of moisture, thus producing a sheet in suitable condition for successfully passing the same through the succeeding drying processes unaided by mechanical compression.

5. The process of making paper which consists in forming a layer of pulp, extract ing free water or excess moisture therefrom by vacuum, and continuing the extraction of moisture and drying of the sheet by vacuum assisted by the drawing of heated air through the sheet.

6. The improvement in the art of making paper which consists in reducing a layer of pulp to a damp Web or sheet by vacuum, forcing additional volumes of air through the sheet until it is in condition for pressing, and applying heated air to the sheet before passing same over finishing driers.

7. The improvement in the art of making paper which consists in reducing a layer-of pulp to a damp web or sheet by vacuum, forcing additional volumes of air through the sheet until it is in condition for pressing, and pressing the sheet and applying heated air thereto before passing same over finishing driers.

8. The improved process of drying paper in the making thereof from pulp which consists in removing moisture from the sheet by drawing air therethrough by vacuum and applying heated air to and drawing same through the sheet.

9. The improvement in the process of drying paper which consists in drawing large volumes of air through the sheet by a plurality of suction-rolls acting successively upon the sheet, so as to effect the extraction of the water without the aid of mechanical compression by absorption and physical contact with currents of air passing through the sheet.

10. The improvement in the process of drying paper which consists in drawing large volumes of air uniformly through the sheet by application of vacuum successively to opposite sides of the sheet. whereby the moisture is extracted and carried off by absorption and physical contact with currents of air passing through the sheet and without the aid of compression.

11. The improvement in the process of drying paper which consists in first passing large volumes of air through the sheet and second passing large volumes of heated air through the partly dried sheet.

12. The method of impregnating paper with matter for coloring, sizing and the like, during the process of manufacturing the paper, consisting in drawing air laden with such matter through the sheet.

13. In a paper-making machine, the combination with a making-wire on which liquid pulp forms into a sheet or layer, of a suction-roll at the delivery end of the wire, and a suction-roll beyond the wire on which the sheet is taken after leaving the wire, with means for maintaining vacuum in said rolls for drawing air in large volumes uniformly through the sheet, so as to effect the extraction of the water without the aid of mechanical compression by absorption and physical contact with currents of air passing through the sheet.

14. In a paper-making machine, the combination with a making-wire on which liquid pulp forms into a sheet or layer, of a plurality of sucti0n-ro1ls over which the sheet is taken, one at the delivery end of the wire and another arranged to take the sheet therefrom, so as to effect the extraction of the water without the aid of mechanical compression by absorption and physical contact with currents of air passing through the sheet.

15. In a paper-making machine, the combination witha making-wire on which liquid pulp forms into a sheet or layer, of a plurality of suction-rolls over which the sheet is taken, one at the delivery end of the wire and another arranged to take the sheet therefrom, and means for applying heated air to the sheet opposite one or more of said rolls.

16. In a paper-making machine, the combination of a plurality of suction-rolls arranged to operate successively upon the sheet, andmeans for maintaining heavy uniform vacuum therein.

17 In a paper-making machine, the combination of a plurality of suction-rolls adapted for drawing air in large volume through the sheet and arranged to operate successively upon the sheet and on opposite sides thereof, so as to effect the extraction of the water by absorption and physical contact with currents of air passing through the sheet and without the aid of mechanical compression.

18. In a paper-making machine, the combination of a making-wire, a suction-roll at the end of the wire, a suction-roll beyond the wire, with means connected with said suction-rolls for maintaining high uniform vacuum therein, sufficient to extract the water and produce a sheet in suitable condition for successfully passing the same through the succeeding drying processes by absorption and physical contact with currents of air passing through the sheet without the aid-of mechanical compression.

19. The process of treating paper in a continuous web in the manufacture thereof from pulp, which consists in drawing moisture from the sheet by drawing air in large volume and uniformly therethrough by vacuum, and applying color or like substance to'the sheet while being subjected to the vacuum. 20. The improvement in the art of makng paper which consists in forming pulp lnto a sheet or layer on a making-wire, removing moisture from the sheet by drawing air uniformly through the sheet by vacuum, and water marking the sheet by means of a type carrying roll applied to that portion of the sheet which is subjected to vacuum.

21. The improvement in the art of making paper without using felts or presses for water expressing purposes which consists in passing the web or sheet over one or more suction-rolls in which vacuum is maintained adapted for drawing air in large volumes uniformly through the sheet, and then passing the sheet to and over drying rolls.

22. The improvement in the art of making paper which consists in effecting its preliminary drying by extracting moisture from the sheet by drawing large volumes of air uniformly through the sheet, and smoothing the sheet by one or more smoothing or friction rollers and passing the sheet through the finishing driers' In testimony whereof I affix my signature, in presence of two witnesses.

WILLIAM H. MILLSPAUGH.

Witnesses:

J. A. BAILEY, C. L. MIELKE. 

